Isoxazol-5-ones as Strategic Building Blocks in Organic Synthesis

Abstract

Isoxazol-5-one rings have been identified as relevant motifs in drug candidates, agrochemicals, and materials. Furthermore, this heterocycle has been also applied as a versatile building block for the preparation of a variety of densely functionalized molecules. This short review will present the most representative applications of isoxazol-5-ones in organic synthesis while discussing their properties and reactivity.

1 Introduction

1.1 General Aspects

1.1.1 Tautomerism

1.1.2 Importance: Natural Products Isolation, Biological Activity, and Materials

1.1.3 Preparation Methods

2 Isoxazol-5-ones in Organic Synthesis

2.1 General Reactivity

2.2 Specific Examples

2.2.1 Alkylation Strategies

2.2.2 Alkyne Synthesis

2.2.3 Annulation Reactions

2.2.4 N–O Bond Insertions

2.2.4.1 Preparation of 1,3-Oxazin-6-ones

3 Conclusions

Key words

isoxazol-5-ones - heterocycles - decarboxylation - alkynes - 2H-azirines - pyridines - 1,3-oxazin-6-ones

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